Answer:
Scientist come to know about the land feel by various measures such as quantity of methane gas, quantity of radioactive materials, etc. They collect data from a particular area and checks it whether it is under critical range or not.
Explanation:
Land-filling is a process by which all the waste which is solid is buried under the ground. It is also a type of land pollution. It degrades the land quality. The land is no more fertile to grow crops. some of the waste are also radioactive which harmful effect the animals and plant living in that area. It also tends to have the humans living nearby that area. this area is also capable of creating methane gas which is very explosive in nature.
Scientist plays an important role for finding out the critical condition of land. They also have instrument which are very helpful for finding out the critical range of the radioactive materials.
Hernando De Soto was the first known explorer
The answer is... The Common Cold!
"Colds" ate generally caused by two specific viruses - rhinovirus and coronavirus
Answer:
Ligand-receptor interaction is the first interaction that triggers cell signalling.
Ligands are the hormones, drugs or neurotransmitters that specifically bind with receptors present in cell surface to initiate cell signalling. Ligand binding to the receptor is reversible. Binding of the ligand to the receptor can activate or inactivate receptor. Activation may lead to cell signalling pathways. Inside cells, there are secondary molecules which on activation starts a cascade of reactions. which in-turn regulate the function of the ligand molecule.
At first, the activated receptor relates with G proteins molecules in the cell.
before the ultimate physiological effect of the ligand on the cell's behavior is produced Therefore, the cellular signaling starts as soon as the first messenger (the ligand) binds to its receptor.
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